DNS on Windows Server 2003, 3rd Edition

7. Loss of Network Connectivity

Though the Internet is more reliable today than it was back in the wild and woolly days of the ARPANET, network outages are still relatively common. These failures usually look like poor performance:

C:\> nslookup nisc.sri.com. 
Server:  terminator.movie.edu 
Address:  192.249.249.3 

DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 4 seconds.
DNS request timed out.
    timeout was 8 seconds.
*** Request to terminator.movie.edu timed-out

Using nslookup, you can look up the names and addresses of the name servers your name server needs to talk to in order to resolve the name:

C:\> nslookup
Default Server:  terminator.movie.edu
Address:  192.249.249.3

> set type=ns
> sri.com.
Server:  terminator.movie.edu
Address:  192.249.249.3

Non-authoritative answer:
sri.com nameserver = ns.sri.com
sri.com nameserver = nsf.algx.net
sri.com nameserver = ns1.sri.com

ns.sri.com      internet address = 128.18.30.66
ns1.sri.com     internet address = 128.18.30.65
> com. Server: terminator.movie.edu Address: 192.249.249.3 Non-authoritative answer: com nameserver = j.gtld-servers.net com nameserver = k.gtld-servers.net com nameserver = l.gtld-servers.net com nameserver = m.gtld-servers.net com nameserver = a.gtld-servers.net com nameserver = b.gtld-servers.net com nameserver = c.gtld-servers.net com nameserver = d.gtld-servers.net com nameserver = e.gtld-servers.net com nameserver = f.gtld-servers.net com nameserver = g.gtld-servers.net com nameserver = h.gtld-servers.net ...